Art of cracking hydrocarbons



July 13 1926.

E. C. HERTHEL El' AL ART OF CHACKING HYDROCARBONS Filed Nov. 20, 1924 TMO w SOSA riunita July is, 192s. i

UNITED STATES 1,592,489 PATENT OFFICE.

EUGENE C. HERTHEL, F CHICAGO, ILLINOIS, LND EDWLEDW. ISDH, 0F LOCUS!! VALLEY, NEW YORK, LSBIGNORS TO BINCLAIB BEFINING GUHPANY, DI CHICAGO.

ILLINOIS, A CORPORATION 0F HAUTE.

application ma november au, im. `mm mi. 750.990.

This invention relates to an im rovcd method and apparatus for cracking envier hydrocarbon oils for the roduction of lighter und lon-er boiling hi rociirbon oils,

6 such as gasoline or pressure distillate. More particularly, this invention relates to improvements in methods of crackin li drocarbon oils in which the oil is circo ated from and to a bulk supply tank through a l0 heater, und to an improved arrangement and construction` of apparatus for carrying out cracking proccssesof this character.

In circulatory pressure stills where the oil is heated in a tubular heater and circulated from and to a bulk sup ly tank, the heat is a plied to thc oil whi e it -islieing circulated) throu h the heater solthnt the oil entering the ulk supply tank from the heater is at a somewhat higher temperature W than that of the oil into which `it is introduced in the bulk supply tank; Cracking may take place to a greater or less extent throughout the body of oil in the bulk supply tank. The se eration of cracked va- 3|' pors take place in t e bulk suppl tank and these vapors are withdrawn usual v through -a reflux tower to ii condenser. ere ne` tire circulation of the oil through the heaterA from and to the bulk supply tank is effected, the circulatin stream of oil maintains the entire body o -ol in the bulk supply tank in agitation to n greater or less extent, wit-.li` resulting turbulence `which interferes with the separations ol cracked .va ors with the result that the oil withdrawn rom the bulk supplyiank and recirculated .through the heater `may still contain vaporizable constit-uents which has not had an 'opportunity of separating in the bulk supply tank before the oil is recirculated. A

According to the present'invention, this turbulence or eddying of oil in the bulk sulpply tank, `due to the rapid intlow of hot oi and vapors from the heater and the rapid circulation of the oil, is prevented or greatly reduced, so thatthe 'separation of cracked vvii rs is faciliteted,. and so thatithe recircu ation of cracked vapors with the oil from the bulk supplytank throulgh and to the 5 heater is prevented or great reduced.

The invention includes bot an improved arrangement and construction of apparatus for .cracking oils and also an improved of 4the bu oil in the. hulk supply tank is facilitated, and

so thin; the oil ivuch goes down 'into the lower part of the bulk supply tank beneath the bullies is relatively` free from 'va riziible cracked constituents, and so that t e oil which is withdrawn from the bulk supply tank and circulated through the heater is iilso relatively free from such vaporizable cracked constituents at the time it enters heater. In the improved process of the invention, the oil is circulate( from the bulk supply tank through theheater and buck to the hulk supply tank and is 'caused to undergo stratification because of the baille arrangement in .the bulk supply tank and the cracked vapors arc for the most part if not entirely removed from the upper layers or strata of the oil in the bulk su ply tank and so that such eddying or turbuiiince as exists is largely confined to the upper layers above the battles into which the return vline or lines from the heater discharge. During this improved inetliod of circulation, the active vii-porizlng and the eddying 'or turbulence of .the oil are largely if not entirely confined 'to these upper layers or strata above the bullies while the oil which flows downwardly ast the ballles to the lower part supply tank is relatively ree f rom vaporizitble constituents and is rela.- tively uiesc'ent so that a better op crtunity is provided for the separation o further amounts of vaporizable constituents ther'efrom, because of the greater quiescence, and so that a Better opportunity is also provided for the separation out in the bottom of the bulk supply tank. of particles carried in suspension inthe oil. und which mi ht othern. e. because of the edrlyim1r or tur u-l lcnce of the entire body of oil in tlie bulk around or -upper and more tur sup ly tank, be carried in suspension again thrdhgh the heater.

In the apparatus of the invention, the bullies or their uivalents are arranged to permit free circu ation of the unva rized oil in a generally downward direction through the bulk su ply tank from the Eulent layers to the lower and more quiescent layers, while largely confining the liberation of vapors to the up r part or layers of the charge in the bu su pl tank. The bellies do not interfere un'tliJ e circulation of the oil from the bulk supply tank to the heater and back to the bui supply tank, but their main function is to control and regulate to a greater or les extent the nature' 'and character of the circulation within the bulk supply tank itself and to cause stratification so that the liberation of vapors is largely confined to the upper layers of oil in the bulk supply tank. The turbulence or eddyi due to the introduction of the hot oil an vapors from the heater is also largely confined to the upper portion of the charge in the bulk su pl tank, while the unvaporized oil, relative y free from vapors or constituents tending to vaporize in the bulk supply tank, settles or flows to the lower part of the bulk suppl tank where it is relatively quiescent a-n ee from disturbing eddying and tubulence. The crosseoctional area of the bulk sup ly tank being much larger than that of t e circulntin lines to and from the heater, the rate 0 How downwardly in the bulk supply tank from the point of reintroduction of oil from the heater to the point of withdrawal of oil flowing to the eater is relatively slow as compared with the rate of circulation throu h the heater. Because of this relatively s ow circulating of the charge as a whole through the bulk supply tank, and because of the stratification 1n the charge brought about by the bellies or their equivalex-lts, the bulk supply tank charge can be considered as havin a generally ownward How around the ba es and aty a gently reduced rate, and the portion of e charge which has flowed downwardl around and beneath the bellies is in the re ativel quiescent state `above referred to. In t 's-way a more complete separation of the va rs andili ht cracked constituents is elec in the bik supply tank and the oil recircu lated to the heater is practically flee from such constituents.

The present invention accordingly pre vents or inhibits very largel the eddying or turbulence which might ot erwies prevent efFective separation of cracked vapors and cause them to be carried again through the heater before sucient opportunity for their se eration has been provided.

e invention is of more or less general tively application to circulatory pressure stills in w ch there is circulation from the bulk Sup ly tank to and through a tubular heater an hack to the bulk suiply tank. Circulaf tory rassure stills o this kind can be mo ed in their construction by the provision of bales suitably arranged in the bulk eupplytankto proven objectionable eddying or turbulence and'to bring about the desired stratification so that the lower levels or layers of oil in the bulk supply tank, fromy which the oil is withdrawn for recirculation through the heater, am relaquiescent. A still of this general construction is described and illustrated in UTS. Letters Patent to the Sinclair Refining Company, overnber 19, 1918, on the application of Edward W. Isom, and the present invention will be more particularly described in connection therewith.

In carrying out the invention in a circulatory pressure still provided with a reflux tower, the reflux may be returned and introduced for example into the stream of oil circulatin from the bulk supply tank to the heater. ere fresh feed is introduced durmg the progress of the operation, it may, in a similar manner; be introduced i'nto the circulating stillcharge at a place where the charge is relatively free. from vapors and li lit cracked constituents, and initially circu ated to the, heater without being circulated through the turbulent vaporizmg zone in the bulk supply tank. Where fresh feed is employed to promote or assist the reflaringl operation by introduction into direct contact with the vapors escaping from the bulk su ply tank; the reflux and admixed feed may returned together to a cooler part of the still chae; Owing to the fact that the hottest oil m the heater enters the bulk supply tank above the bellies and admixes with the oil in the up r portion of the bulk suppl tank, it will e evident that the oil strati 'ng and circulating slowly to the lower part of the'bulk supply tank will be relatively cooler than that in the upper portion. When the reflux or the feed, or the admixed reflux and feed, is introduced into the lower portion of the still, it will thus'come in contact with oil at a. somewhat lower temperature than that in the u per portion of the bulk supply tank; whi e if the redux, or feed or admixed redux and feed, is introduce into the rculating line between the bulk sulpply. and the heater, it will edmix with oi which is also at a lower temperature and which is relatively cracked constituents.'

e present invention is of s ecial-value and application in connection wit continuous or eem1-continuous cracki processes in which fresh oil is introduced into the still charge,

free from vaporizable Nu 1,285,200, had

ing operation. In

sup ly tank and in which tar is withdrawn from the still charge, during the progress of the crack carrying out the present invention in connection with such methods of operation, the tar is withdrawn from the lower and cooler part of the still charge. The tar, for example, may be withdrawn from a l wer stratum of the oil in the bulk supply tank which is relatively free from vapors and light. cracked constituents and which is relatively free from turbu ence. Stratification of the charge of oil in the bulk promotes the eparation of the taruden part of the still char e and assists in concentratinthe tarry constituents in the stratum from w ich tar is drawn oli'. At the same time, by conlining vaporization and vturbulence to the upper part of the charge in the bulli supply tank, and by withdrawing the tur from the oiver, q uiet and cooler part of the charge therein which is relatively free from vapors and light cracked constituents, and withdrawal of vapors or light cracked constituents with the tar is prevented or greatly reduced.

The invention will be further described in connection with the accompanying drawing illustrating an embodiment of the apparatus of the invention adapted for carrying out the process of the invention, but it is intended and will be understood that the invention is illustrated thereby and not limited thereto.

In the accompan Fig. 1 represents, iagrammatically and partly in section and partl in elevation, ii pressure still system embo ying the invention and adapted for carrying out the inrention.

Fig. 2 is a section on line 2 2 of Fig. 1. and

Fig. 3 is a view similar to Fi 2, illusti'ating'a dierent. arrangement o the bulk supply tank of the pressure still.

l ie pressure still illustrated in the drawing comprises a bulk supply tank 1,L a heater consisting of a bank of tubes 2 vertically iirranged in the heatin flue of the furnace 3, a circulating pump and circulating lines 6 and 7 connecti in order, the supply tnnk,tlie circu ating pump, the lower end of the heating tubes, the upper end. o the heatin tubes and the bulk supply tank.

Arrangi above the bulk supp y tank is a influx tower 8 having: series of therein. The vapors li rated in the bulk supply tank escupe to the lower end of the reflux tower through the vapor line 9. return reflux line 10 is provided for returning reflux from the bottom of the tower to the pressure still. The vapors from the rellux toiver escape throu b Ythe vapor line ll drawing,

to the condenser 12 iv ich discharges into the receiver 13 from which the condensed distillate is withdrawn through the outlet f stratum ofptilie oil in the bulk sup illes above the 14 and from which the uncondensed vapors ilusid gases are withdrawn through the outlet A feed line 16 isV rovided for introducirlo' fresh charging stoc into the upper end oli the reiix tower in direct contact` with the vars therein, and connection 17 is arranged or introducing cool oil into the circulating stream of oil through the bearings of the circulating pump. l tar draivoi for withdrawing tar during the progress of the cracking operation is shown at 18, and a connection 19 is provided for pumping out and initially charging the still.

The resem-e may bc reduced and regulated by t ie regulating valve 20 arranged betiveen the reflux tower and the condenser, or the condenser muy he operated at substantially the pressure prevailing in the still and the pressure may be reduced and regulated by suitable regulating valve arranged be rond the receiver.

n the bulk su ply tank of the pressure still illustrated, oiis withdrawn through the drop leg 5 and is circulated upwardly through the heater and back to the bulk su pity tank through a pair of connections e drop leg 5 opens into the lower part of the charge in the bulk supply tank and is arranged to withdraw oil from the lower and cooler part of the charge therein. The liot oil and vapors from the heater are introduced into the upper part of the charge in the bulk supply tank.

Arranged eloir the inlet connections 7 in the hulk supply tank, and above the outlet to the drop lef; 5, are a series of horizontal haillcs 21, a imi-n as three in number, extending throuchout the length of the bulk supply tank. lhese haliles, staggered as shown, tend to divide the charge in the bulk supply tank into an upper stratum A and a lower stratum B while nevertheless pernrit,l ting a free circulation of unvaporized oil from the upper stratum to the lowerstratuni.

The hot vapor-laden and vaporizing oil from the heater is introduced into the charge in the bulk su ply tank above the bellies and the bellies tens to confine the turbulence arid ulk eddyn due to the introduction of the hot rs to the upper part or upper ly tank. The battles also assist in continn t e libera tion of va ors to that part o tho charge illes and in conlining the hot vapor-laden oil rom the heater to the upper part of the charge where vapors more oil an va A readily escape. and assist in promotin a more coin lete liberation of the vappriza le constituen a in the hot oil from the eater.

Theballles also tend to maintain a relatively quiet and cooler zone in the lower part of the charge in the bulk supply tank from which the iinvaporized oil is recircih lated through thc heater. The oil in this fdl and

lower and cooler stratum is relatively free from va ors and light cracked constituents. Redux, rom the relux tower is returned through the redux return line 10 to the upper end of the drop leg 5 where it is drawn by the suction of the circulating pump .downwardly through the drop leg in admixture with cooler oil from the lower art of the bulk supply tank -and circulated Back to the bulk supply tank' through the heater. The -rellux is thus returned to the heater in admixture with unvaporized oil from the bulk supply tank without passing through the turbulent zone in the uEper part of the bulk supply tank in whic vapors are being liberated from the oil from the heater and where it would' otherwise be subjected to a higher tem rature, b contact with the hot oil res from the eater, with resulting vaporization and escape of vaporiaed constituents,

without being resuhjeeted to the cracking tem rature in the heater. Fresh charging,

stoc introduced into-the redux tower, after passing thi-ou h the tower, is-introduced in admixture wit the reilux into the stream of cooler oil circulating from the bulk supply tank to the heater.

The tar drawoi 18 is provided for withcracking o ration, and is arranged to-withdraw tar m the lower part of the charge in the bulk supply tank or lower stratum The terry constituents do not tend to vaize, and, due to the provision of the ailles, tend to collect with the unvaporized -oil in the lower part of the charge belowy Aconnections the bellies. This lower zone is relatively quiet and the oil therein is.not continually intermixed with hot oil .fresh from the heater so that an opportunity is provided for the escape of such readily va orizable constituents as are carried below t e ballles and so' that the oil below the bales becomes substantially free l m vapors and like cracked constituents. The battles also tend to increase the concentration of the tar constituents in the lower stratum in the bul supply tank by promoting a more complete vaporization of the light constituents.

The function of the bales is to promote a stratification of the still` charge in the bulk supplytank and to divide it into im up r zone, to which active vapor-ization and tur ulence due to the introduction of hot oil and vapors from the heater is confined, and a lower cooler zone to which the unvnporized oil is free to circulate from the upper zone. The bellies may be constructed of metal or other suitable material free' from catalytic ell'ect upon the still charge.

In operation, the still is charged, with gas oil for example, and brought to cracking conditions of temperature and pressure, distillation is begun. With ordinary per square inch may be rawing tar during the progress of the' gas oil charging' stocks, ressures, for example, in the neighborhoo of to 125 lbs. emlloyed; or, with lighter charging stocks, su as a kerosene character stock, for example, pressures up to as high as 300 lbs. per square inch or higher 4ma be em loyed. Fresh feed is introdncted :giu l1 t e .reflux tower intldirectl. con ac wit t e vapors escap' t ro the reflux tower from the bulk gli?) 1y tair, and the resulting admixed feed an reflux is introduced into the circulating stream of oil flowing from the lower part' of .the bulk supply tank to the heater. The circulating oil is passed upwardly through the heating tubes from which the hot oil and va rs are discharged into the bulk suppl tan above the The vapors are or the most part liberated from the hot oil in the upper part of the bulk supply tank and escape through thereux tower, while the unva porized oil and tarry constituents llow to the quiet and cooler zone in the lower 4part of the bulk supply tank below the baffles.

In carrying out a continuous cracking operation in the still illustrated. tar is withdrawn'froxn t in the bulk supply tank throughthe tar draws oil' 18 in amount suicient to maintain the concentration of terry constituents in the still charge below an objectionable point, and sufficient fresh charging stock is introduced into the still to maintain the charge therein.

In the dilerent form of apparatus illustrated in Fig. 3, a screen 22 1 s arranged in the bulk sufply tank below the circulating rom the heater and above the outlet to the circulating connection to the heater. A screen, arranged as illustrated, is useful in inhibitingv turbulence in the lower part of the still charge and in confining the main liberation of vapors to the upper Vpart of the still charge. A screen, however, is not as advantageous as bailles of the type illustrated, since there is apparently a greater tendency for circulation of the hot oil and vapors from the heater therethrough fore vaporization is substantially completed, so that stratification is not promoted as effectively as with a baille or bellies. If the concentration of terry constituents in the still charge exceeds the saturation point and precipitation begins, a screen also tends to choke or clog with precipitated carbon and tarr matter.

One ci, the important advanta es of the present invention is that it su antially revente or materially reduces over-crackmg of constituents desirable in the pressure distillate. Overcracking tends to cause objectionable unsaturation and likewise resuits in the conversion of increased amounts of the chargin stock into incondensible gases. Where e agitation due to the inhe lower part of the charger Lecciso troduction of the hot oil and vapors circulating from the heater into the bulk sup- Ely tank is unrestricted, the consequent turulence tends to carry some vapors and light cracked constituents again through theheiiter with the circulating oil before they caiibe' liberated in the bulk supply tank, resultin in further subjection o these vapors an light cracked constituents to the cracking temperature in the heater with conse nent overcracking. By causi a strati cation of the stil charge in theulk supply tank, and by confining the liberation of vapors and the turbulence due to the introduction of hot oil and vapors from the heater largely to the uper stratum, a more com lete separation of t e vapors and light crac ed constituents is ellected in the bulk suppl tank, and objectionable overcracking o auch constituents as might otherwise be carried along with the circulating oil is avoided.

The invention has been articularly described in connection with t e construction and operation of a circulatory still in which the circulation was mechanically promoted by u pump. The invention is also useful in connection with circulatory crackin stills in which circulation is maintain without mechanical circulntin means. although to a lesserv degree. ere a circulatin pump is employed, com aratively rupi circulation is effected and t e turbulence in the bulk supply tank andthe tendency to car vapors and light cracked constituents with the circulatin oil before they can be liberated is relative y increased. Where a circulating pump is not employed, this tendency is no as marked, but the o eration of such circulatory pressure crac ing stills may nevertheless be improved by causing e stratification of the charge in the bulk supply tank.

It will thus be seen that the invention provides for improvements in the constructions land in the o eration of circulatory preure stills, an particularly stills in which a large charge of oil is maintained in a bulk supply tank and circulated therefrom a tubular heater and back to the bulk supply tank. It will also be seen that the invention is of more or less neral application to charging stocks of di erent kinds and to ressurc still operations carried out at di erent temperatures and pressure depending upon the charging stock which is used for char ing the pressure still. It will also beevi ent that bafarrangements of various kinds can be use tion and to prevent the undesired turbulence and eddying` obtained in preure stills in which there is no impediment to the turbu lence and eddying in the bulk supply tank. It will also be evident that the pressure still to bring about the desired stratica embogying the invention and' the process c arri out therein are capable of modification in various ways, such as the reintrodnction of redux, the withdrawal of tar, the introduction of additional feed, and the carrying out of the pressure distillation as a continuous operation over long periods of time, the improvement in the operation of the crackin process bei favorable to such continu Aand proloiigligl operation.

It will also be evident that variations and modifications can be made in the construction of the pressure still and iu the method of operation without departing from the spirit and scope of the invention.

We claim:

1. A method of cracking hydrocarbon oils, which comprises circulatingr the oil from and to a bu k supply tank t ough a heater meintainin a large body of oil 1n the bulk supply t heatin the oil to a cracking temperature in the ieater causing a stratiication of the oil in the bulk supply tank by obstructin the free flow of oil downwardly in sai body and thereby conlinin the turbulence due to the introduction o the oil from the heater into the bulk su sly tank to the upper stratum, and wit i'awing oil from the lower stratum for recirculation throu li the heater.

2. A method o cracking hydrocarbon oils, which comprises mechanically circulating the oil from and to a bulk supp y tank through a heater maintaining a arge bod of oil in the bulk supply tank, heating t e oil to a cracking tem erature in the heater, causing a stratification of theoil'in the bulk suply tank b obstructing the free flow of oil ownwa y in said body and thereby continin the turbulence due to the introduction of t e oil from the heater into the bulk supply tank to the upper stratum, and withdramn oil from the lower stratum for recirculation through the heater.

3. A. method of cracking hydrocarbon oils, which comprises circulatin the oil from and to a bu k supply tank rough a heater maintainin a large body of oil in the bulk supply tan heatin the oil to a. crackin tem rature in the ester causing a stratilication of the oil in the bulk supply tank by obstrtin the free flow of oil deurn-4 wardly in sai body and thereby confining the turbulence due to the introduction of the oil from the heater into the bulk supply tank to the upper stratum, subjecting the vapors escaping from the bulk supply tank to a reiluxing operation, returning reflux to the oil in the lower stratum, and withdrawing oil from the lower stratum for recirculation through the heater.

4. A method of cracking h drocarbon oils which comprises circulatin t e oil from an to a bulk supply tank t rou h a heater maintaining a large body of oi in the bulk supply tank, heating the oil to a cracking temperature in the heater, causing a stratification of the oil inthe bulk supply tank by obstructingi the free flow of oil downwardly insai body and thereby confinin the turbulence due to the introductiouof the oil from the heater into the bulk supply tank to the upper stratum, withdrawing oil from the lower stratum for recirculation through the heater, subjecting the vapors escaping from the bulk supply tank to a. re- Huxin operation, and recirculating the reliux rom the refiuxing operation through the heater with the oil from the lower stratum.

5. A method of cracking hydrocarbon oils, which comprises umping the oil from a bulk su ply tank t rough a heater and back to the ulk supply tank, heating the oil to a cracking temperature in the heater maintaining a large body of oil in the bulk supply tank, cuusing a stratification of the oil in the bulk supply tank by obstructiinr the free flow of oil downwardly in said llaody and thereby confining the turbulence due to the introduction of the oil from the heater into the bulk supply tank to the u per Stratum, subjecting the vapors escaping rom the bulk supply tank to a ieliuxing operation, and pumping the reflux from the reiuxing operation with oil withdrawn from the lower Stratum through the heater.

6. A method of cracking hydrocarbon oils, which comprises circulating the oil from and to a bulk supply tank through a heater maintaining a large body of oil in the bulk supply tank, heatinv the oil to a cracking temperature in the eater, causing a stratification of the oil in the bulk supply tank by obstructin the free flow of oil downwardly in said bogdy and thereby confining the turbulence due to the introduction of the oil from the heater into the bulk su ply tank to the upper stratum, subjecting t e vapors escaping from the bulk supply tank to a reiiiixin operation in direct contact with fresh c urging stock, and circulating the reflux and admixed char 'ng stock through the heater with oil wit drawn from the lower stratum.

7. A method of cracking hydrocarbon oils, which comprises circulating the oil from and to a bulk supply tank through a heater maintaining a large bod 1 of oil in the bulk supply tank, heating tlie oil to a cracking temperature in the heater, causing estratification of the oil in the bulk sup ly tank by obstructin the free flow of oil downwardly in said boldy and thereby confining the turbulence due to the introduction of the oil from the heater into the bulk supply tank to the upper stratum, withdrawin tar from the lower stratum, and recirciating oil withdrawn from the lower stratum through the heater.

g supply ta 8. A method of cracking hydrocarbon oils, which comprises circulatin the oil from and to a bu k supply tank t rough a heater maintainin a large body of oil in the bulk heatin the oil to a cracking temperature in the eater, causin a stratitication of the oil in the bulk suppy tank by obstructing the free How of oil downwardly in said body and thereby conlinin turbulcnce due to the introduction of oil groin the heater into the bulk su ply tank tothe upper stratum while permitting circulation of unvasorized constituents to the lower stratum, an withdrawing oil from the lower stratum for recirculation throu h the heater,

9. A method of cracking hydrocarbon oils, which comprises circulating the oil from and tc a bulk supply tank through a heater maintaining a large body of oil in the bulk supply tank, heatin'g the oil to a cracking temperature in the heater, causing a stratification of the oil in the bulk supply tank by obstructing the free flow of oil downwardly in said body and thereby connin turbulcnce due to the introduction of oil rom the heater into the bulk supply tank to the upper stratum while permitting circulation of unvaporized oil and associated tari-y constituents to the lower stratum, withdrawing tar from the lower stratum, and recirculating oil withdrawn from the lower stratum through the heater.

10. A method of cracking hydrocarbon oils, which comprises circulating the oil from and to a bulk sa ply tank through a heater maintaining a lparge body of oil in the bulk supply tank, heating the oil to a crackin" temperature in the heater, causing a stratication of the oil in the bulk su ply tank by obstructing the free flow oiP oil downwardly in said body and thereby conlning the turbulence due 'to the introduction ot the oil from the heater into the bulk supply tank to the upper stratum, withdrawin oil from the lower stratum for iiecircultion through the heater, and withdrawing tar from the operation from the lower stratum and supplying fresh charging stock.

11. An apparatus for distilling hydrocarbon oils under ressure, comprising a bulk supply tank an a heater, circulating oonnections from the lower part of the bulk supply tank to the heater and from the heater to a hi lier part of the bulk sup 1y tank, and ballimeans for confining ,turbulcnce to the upper stratum of oil in the bulk suplply tank arranged in the bulk supply tan between the circulatin connections from the heater and the circuiting connections to the heater below the normal liquid level therein.

12. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank an a heater, circulating conllO nections including a pump from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and baille means for confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein.

13. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, battle means lor confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein, a reflux tower communicating with the vapor space in the bulk supply tank and connections for returning relluX therefrom to a point between the lower side of the haflle means and the heater.

14. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, baille means for confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein, a reflux tower communicating with the Vapor space in the bulk supply tank, means tor introducing fresh charging stock directly into the reflux tower, and connections for returning reflux and admixed charging stock therefrom to a point between the lower side of the baille means and the heater.

15. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, baille means for confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connectionsfrom the heater and the circulating connections to the heater below the normal liquid level therein, and a connection for withdrawing tar from the bulk supply tank below said baille means.

16. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the bulk supply tank between the circulating,connections trom the heater and the circulating connections to the heater below the normal liquid level therein for causing a stratification of oil in the bulk supply tank and for contining turbulence to the upper part of the bulk supply tank.

17. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections including a pump from the lower part ot the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein for causing a stratification of oil in the bulk supply tank and for confining turbulence to the upper part of the bulk supply tank.

18. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the bulk supply tank between the circulating connections t'rom the heater and the circulating connections to the heater below the normal liquid level therein for preventing turbulenc'e in the lower part of the bulk supply tank.

In testimony whereof we affix our signa.- tures.

EUGENE C. HERTHEL. EDWVARD 1V. 'ISOM.

nections including a pump from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and battle means for confining turbulence to the upper stratum ot' oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein.

13. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part ot' the bulk supply tank, baffle means for confining` turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein, a reiiux tower communicating with the vapor space in the bulk supply tank and connections for returning reflux therefrom to a point between the lower side of the bafile means and the heater.

14. An apparatus for dist-illing hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, baille means for confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein, a reflux tower communicating with the vapor space in the bulk supply tank, means for introducing fresh charging stock directly into the reflux tower, and connections i'or returning reiiux and admixed charging stock therefrom to a point between the lower side of the baille means and the heater.

15. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, baffle means for confining turbulence to the upper stratum of oil in the bulk supply tank arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein, and a connection for withdrawing tar from the bulk supply tank below said baflie means.

16. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the bulk supply tank between the circulating,connections from the heater and the circulating connections to the heater below the normal liquid level therein for causing a stratification of oil in the bulk supply tank and for Confining turbulence to the upper part of the bulk supply tank.

17. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections including a pump from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein for causing a stratiiication of oil in the bulk supply tank and for confining turbulence to the upper part ot' the bulk supply tank.

18. An apparatus for distilling hydrocarbon oils under pressure, comprising a bulk supply tank and a heater, circulating connections from the lower part of the bulk supply tank to the heater and from the heater to a higher part of the bulk supply tank, and means arranged in the 'bulk supply tank between the circulating connections from the heater and the circulating connections to the heater below the normal liquid level therein for preventing turbulentie in the lower part of the bulk supply tan t.

In testimony whereof we atiix our signatures.

EUGENE C. HERTHEL. EDWARD 1V. 'ISOM.

D s o A l M E R 1,592,489.-Eugene C. Herthel, Chicago, Ill., and Edward W. Isom, Locust Valley, N. Y.

ART or CRACKING HYnRocAaBoNs.

Patent dated July 13, 1926. Disclaimer filed November 23, 1928, by the assignee, Sinclair Refining Company.

Hereby enters `this. disclaimer to the method offsaid claims 1, 2, 1,8, 9, and except as applied to the separation from oil reclreulated from .the bulk supply tank through the heater of constituents vaporlzable under the conditions of temperature and pressure prevailing in the bulk supply tank, and to the apparatus of sald claims 11, 15, 16, and 18 except such apparatus m which the h ot oll products from the heater are discharged together through the same circulating connections from the heater to the bulk suppl tank.

[cial Gazette Decem er 11, 1928.]

DISC L Al M E R 1,592,489.71L`uge'ne C. Herthel, Chicago, Ill., and Edward W. 180m, Locust Valley N. Y. ART oF CRACKING HYDRocARBoNs. Patent dated July 13, 1926. Disclaimer filed November 23, 1928, by the assignee, Sinclqir Rejmlng Company.

Hereby enters this disclaimer to the method of Said claims l, 2, 'L 8, 9, and 10 except as applied to the separation from oil recirculated from the bulk supply tank through the heater of constituents vaporizable under the conditions of temperature and pressure prevailing in the bulk supply tank, dnd to the apparatus of said claims 11, l5, 16, and 18 except such apparatus in which the hot oil products from the heater are discharged together through the same circulating connections from the heater to the bulk suppl tank.

[,Oicial Gazette Decem er 1I, 1928.] 

